Unless otherwi se indicated herein, the materials described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
Electronic communications frequently take place over insecure communication channels. Insecure communication channels may include wired and wireless channels as well as encrypted and unencrypted channels. So-called “open”, or unencrypted Wi-Fi networks are often insecure, however, even “security-enabled” Wi-Fi networks, in which wireless transmissions are encrypted, are vulnerable to attacks such as the so-called “man in the middle” attack. Cellular communication networks can also be insecure. For example, third parties may set-up “fake” or unauthorized cellular communication stations that capture and forward cellular communication data. In general, a wide variety of eavesdropping activities may take place within any network infrastructure.
Secure communication may include exchanging information with varying degrees of certainty that third parties cannot intercept and/or decrypt it. Secure communication methods may use shared secrets, for example, as described in G Simmons, “Prepositioned Shared Secret and/or Shared Control Schemes,” Advances in Cryptology—Eurocrypt 1989 (Springer, 1990): 436-467; and D. Catalano, R. Gennaro, and S. Halevi, “Computing Inverses Over a Shared Secret Modulus,” Advances in Cryptology—Eurocrypt 2000 (Springer, 2000): 190-206. Shared secrets present a powerful secure communication tool allowing, for example, parties in possession of a shared secret to encrypt and decrypt data using the shared secret, while any party not having the shared secret cannot decrypt intercepted data. However, initially establishing the shared secret, without also providing the shared secret or information that may be used to ascertain the shared secret to would-be eavesdroppers can present security vulnerability in some scenarios.